Before 1914, nationalism in the Balkan Peninsula

contributed to

(1) resistance by ethnic groups to Austrian rule

(2) campaigns by foreign diplomats against the

use of trench warfare

(3) the inability of countries to make reparation

payments

(4) the rejection of the Versailles Treaty by

combatants

The correct answer is Option A) Resistance by ethnic groups to Austrian rule.

At the time, one of the largest European Empires, the Austria-Hungary controlled large parts of land in the Balkans. However, a small but aggressive resistance was growing based on Balkan nationalism.

However, for much of the early 20th Century this small resistance proved futile and did little to change the stance of Austria-Hungary.

Even after the Balkan Wars, which had effectively ended Ottoman rule in the region and forced Austria-Hungary out of most of the region, the country was still able to hold on to small pockets of rich Balkan areas.

Before 1914, nationalism in the Balkan Peninsula contributed to " (1) resistance by ethnic groups to Austrian rule" but this was often short-lived in many ways.